Roll grinding machine



Jan. 25, 1938. E. HUTCHENS 7 ROLL GRINDING MACHINE Filed Dec. 15, 1934 5 Sheets-Sheet l Mm. w. W J

Jan. 25, 1938. E. HUTCHENS 2,106,215

ROLL GRINDING MACHINE Fil ed Dec. 15, 1934 5 Sheets-Sheet 2 fig 2 Jan. 25, 1938. E, HU C E'NS 2,106,21

I ROLL GRINDING MACHINE Filed Dec. 15, 193: s sheets sh'eef 5 Jan. 25, 193s.- E.- HUTCHENS 6, 5

ROLL GRINDING MACHINE Filed Dec. 15, 1-934 5 Sheets-Sheet 4 ZF WEE-25.5 I fail/4rd XAZCYfi/s Jan. 25, 1938. E HuTcHNs 2,106,215

ROLL GRINDING MACHINE Filed Dec. 15, 1954 5 Sheets-Sheet 5 Pm f inm'mnm fg QB lllllllmmmllnflmllll llllll lllll ll Patented Jan. 25, 1938 UNITED sra'res PATENT OFFICE ROLL GRINDING MACHINE Application December15, 1934, Serial No. 757,620

11 Claims.

This invention relates to a machine for grinding or abrading rollers, such .as rubber print rollers, to provide the same with a smooth and even periphery. The invention includes a process for grinding the rollers whereby the formation of grooves and uneven hill and valley portions is avoided.

More specifically, this invention relates to a machine for grinding rubber print rolls to true and smooth their peripheries and form a smooth working surface thereon. The invention also includes a process for grinding rubber rollers on the machine of this invention.

It has heretofore been proposed to resurface printing rollers by grinding or abrading their working surfaces with an abrasive wheel that travels longitudinally along the roll similar to a cutting tool in a lathe. Machines of this character, however, only grind a surface of the roll of about one inch in width at one time and their travel back and forth over the entire length of the roller requires considerable time.

I have now provided a grinding or abrasive machine to resurface rubber rollers or composition rollers used on printing machines which acts upon the entire length of the roller at one time. The entire resurfacing operation may be completed by my machine within a few minutes. Furthermore, since my machine acts upon the entire length of the roller at one time, it is possible to obtain a truer surface on the roller than was heretofore obtainable.

It is therefore an object of this invention to provide a device for grinding rollers to provide a smooth and even periphery thereon in a short time.

A further object of this invention is to provide a grinding machine for printing rollers that acts upon the entire length of the roller at one time. Another object of this invention is to provide a quick and economical method for surfacing rollers, such as rubber print rolls.

Another object of this invention is to provide an economical process for resurfacing rubber rollers at high speed.

A further object of this invention is to resurface the periphery of a worn print roll to provide a true and smooth working surface thereon.

A specific object of this invention is to provide 0 a high speed machine for abrading the periphery of printing rollers to provide a true and smooth working surface thereon.

Other and further objects of this invention will be apparent from the following detailed description of the annexed sheets of the drawings which disclose a preferred modification of this invention.

0n the drawings: V b

Figure 1 is a broken front elevational view of a machine according to this invention. I 5;

Figure 2 is a broken top plan view of a machine according to this invention. v

Figure 3 is a broken cross-sectional View, with parts shown in elevation, taken substantially along the line III III of Figure 1.

Figure 4 is a cross-sectional view taken substantially along the line IV--IV of Figure 2, with parts broken away.

Figure 5 is a broken cross-sectional view, with parts in elevation, taken substantially along the 1 '5" line V-V of Figure 3.

Figure 6 is a fragmentary side elevation of the right hand side of the machine as shown in Figure 1.

Figure 7 is a fragmentary side elevation of 6" the left hand side of the machine as shown in Figure 1.

Figure 8 is a cross-sectional view, withparts in elevation, taken along the line VIII-VIII of Figure 4. i 25 Figure 9 is a cross-sectional view, with parts in elevation, taken substantially along the line IX-IX of Figure 5.

Figure 10 is an enlarged cross-sectional view taken substantially along the line XX of Figure 9.

Figure 11 is a cross-sectional view taken'sub stantially along the line XIXI of Figure 10.

Figure 12 is a vertical cross-sectional view with parts in elevation illustrating a holding 35 down attachment and showing in dotted lines the change in the positions of the roll feeding and holding devices to accommodate rollers of various sized diameters.

Figure 13 is a fragmentary front elevational 4 view of the holding down device shown in Figure 12.

Figure 14.- is a fragmentary end elevational View of the grinding roller showing the clamping means for securing the abrasive sheet material 45 which is wound around the roller.

As shown on the drawings:

In Figure 1, the reference numeral It! indicates a supporting base upon which the machine is mounted. I-beam members II .and I2, having flanged bases I3, are bolted to the base Ill by means of bolts l4 extending through their flanged bases. The I-beams H and I2 have a very wide web I5 extending across the full depth of the machine so as to form side walls for the machine. 5*

An angle beam I6 is mounted on top of the I- beams II and I2 at the front end of the machine. The base In, I-beams II and I2 and angle beam |6 form the framework for the machine.

A main driving motor is mounted on the base l0 near one end thereof while an auxiliary motor I8 is mounted on the base near the other end thereof. The main driving motor I! rotates a grooved pulley l9 for driving a plurality of V- shaped belts 20 which are disposed around the pulley IS in the grooves therein. The belt 20 in turn drives a grooved pulley 2| which is rotatably mounted on a non-rotatable axle 22.

As shown in Figure 5, the axle 22 extends through bosses 23 and 24 bolted to the I-beams II and I2, respectively, in the web portion |5 thereof by means of bolts 25 and 26 (Figures 6 and '7). The central portion 21 of the axle 22 is provided with an enlarged diameter forming shoulders 28 and 29 at the ends thereof. An antifriction bearing 3|! is held against the shoulder 28 by means of a collar 3| which is threaded on the axle 22. Another anti-friction bearing 32 is held against the shoulder 29 by means of a sleeve 33 disposed around the axle 22. Anti-friction bearings 34 and 35 are disposed within the pulley 2| and serve to mount the pulley in freely rotatable relation relative to the axle 22. The bearings 34 and 35 are held against the sleeve 33 by means of a collar 36 threaded on the axle 22. The collar 36 also serves to urge the sleeve 33 against the bearing 32.

An end portion 2|a of the pulley 2| is detachable from the remainder of the pulley to permit insertion of a grease packing ring 38 for retaining lubricant in the bearings. The end portion 2|a of the pulley 2| is secured to the pulley by means of bolts or other securing means (not shown). The pulley 2| is also provided with a laterally extending tubular portion 39 terminating in an enlarged circular plate 4|] which is bolted by means of bolts 40a (Fig. 9) to an annular supporting member 4| rotatable about the axle 22 on the bearing 32.

A boss 42 rotatably mounted around the axle 22 on the bearing 3|! is provided with a lubricant retainer ring 43 and is secured to another annular supporting member 44. The supporting members 4| and 44 are disposed within a tube or roller 45 and are pressed into integral relation with the roller to drive the same. The roller 45 is provided around its outside periphery with a wrapping 46 of an abrasive material such as sand or emery paper. The pulley 2| drives the roller 45 so that it rotates relative to the axle 22. The axle 22, however, is prevented from rotating by means of a bolt 47 (Figure 1) extending through a transverse hole 48 (Figure 5) at one end of the axle.

As shown in Figures 1, 7 and 8, the auxiliary motor I8 is coupled by means of a coupling 49 to a shaft 49a rotatably mounted in the web l5 of the I-beam member The end of the shaft 49a is keyed to a gear 56 which meshes with and drives a larger gear 5|.

As shown in Figure 8, the gear 5| is secured on the end of a shaft 52 which extends through a bearing boss 53 and through the web |5 of the I-beam A small gear 54 is keyed to the shaft 52 in spaced relation from the web l5. This gear 54 meshes with and drives another gear 55 keyed to a stub shaft 51. A boss 56 of a sprocket gear 19 is also keyed to the shaft 51. The gear 19 drives a chain for a purpose to be hereinafter,

described. The stub shaft 57 is secured to the web |5 by means of a nut 58.

A beveled gear 59 is driven by the shaft 52 and meshes with another beveled gear 60 at right angles thereto. The gear 65 is provided with an off-center pivot opening 5|. An eccentric pin 62 (Figure 1) extends into the opening 6| and is driven by the gear 60. The member 62 has an arm 63 which extends through the web I5 and is pivotally connected to a pair of vertically disposed bars 64 and 65 (Figure 7) by means of a bolt '66. The bars 64 and 65 are pivoted, by means of a bolt 68, around a lug 67 extending from the machine frame. It is evident that the eccentric throw of the gear 60 oscillates the link arm 63 to tilt the bars 64 and 65 about the axis 68. This movement causes a longitudinal movement of the axle 22 which is bolted to the ends of the bars 64 and 65 by means of the bolt 41.

The longitudinal movement of the axle 22 is transmitted to the sanding roller45 through the bearings 30, 32, 34 and 35 which are locked against longitudinal movement relative to the axle. Stop members 69 and 10a are secured on the axle 22 to prevent an unseating of the axle from the bearing bosses 23 and 24 in the I-beam members H and I2, respectively.

From the above description, it is evident that the main driving motor rotates the sanding roller 45 while the auxiliary motor I8 causes a tilting of the bars 54 and 65 to move the axle 22 longitudinally. This longitudinal movement of the axle is transmitted to the sanding roller 45 so that during the grinding operation, the

drum is rotated and oscillated at the same time.

The oscillations preferably are limited to longitudinal movement not exceeding one-half inch in length in each direction. The drum is rotated at a high speed of about 1,200 R. P. M. The oscillations during this time occur about twelve times per minute. It is obvious, however, that the amplitude of the oscillations and the speed of revolution may be varied throughout a wide range.

The flexibility of the V-shaped belts 20 permits the desired oscillation without interfering with the rotation of the sanding roller 45.

A shaft 10 extends across the front of the machine, as shown in Figure 1, and is mounted at the ends thereof in straps TI and '12 secured to the front face of the I-beams H and I2, respectively. Arms 13 and 14 (Figure 1) are keyed to the shaft 10 and support a feeding roller 15 in rotatable relation by means of shafts l6 and I! which extend laterally from the ends of the roller 15. The end of the shaft 16 is keyed to a sprocket gear 11 having a drive chain 18 meshed therearound.

In Figure 8, it has been described that the auxiliary motor i8 drives the gear 55 through a train of gears. A sprocket gear 19 mounted on the same shaft as the gear 55 is driven by the gear 55. As shown in Figure 4, the sprocket gear 19 drives a chain 83 which in turn drives another sprocket gear 8| freely rotatable about the shaft 10. The sprocket gear 8| is keyed to another sprocket gear 82 which latter gear drives the chain 18 to rotate the sprocket gear 11 and the feed roll 15.

As best shown in Figures 1, 6 and '7, a handwheel 83 is rotatably mounted in a housing 84 carried by the machine frame structure on a shaft 85. A worm gear 86 is formed on the shaft 85 within the housing 84 and meshes with a sector gear 81 which is keyed to the shaft 10. A rotation of the handwheel 83 produces a movement of the sector gear 81 which rotates the shaft I9 to raise or lower the supporting arms 13 and I4 and thereby move the feeding roll I5 either away from or toward the sanding roller 45.

The feeding roller is driven in a direction opposite to that of the sanding roller 45, and as will be hereinafter described, the rubber roller to be resurfaced is placed in the nip between the feeding roll and sanding roll. The position of the feeding roll is adjustable to vary the nip or the distance between the feed roll and the sanding roll so that the machine is adapted to operate on rollers of any diameter. The feeding roll is driven by the auxiliary motor I9 while the sanding motor is driven by the main motor II.

As best shown in Figures 1 and 2, a shaft 99 extends half way across the machine near the top thereof. The shaft 99 is mounted at the ends in bosses SH and 92 which are secured to the top angle bar I9. An arm 93 is keyed to the shaft 99 and extends downwardly therefrom for a purpose to be hereinafter described. The end of the shaft 99 is keyed to a bar member 94 which extends laterally from the side of the machine. A second bar member is placed in juxtaposed relation with the member 94 and abuts the same on one flat side thereof. A second shaft 99 is keyed in the member 95 and extends slightly into the member 94 as shown in dotted lines in Figure 2. The other end of the shaft 99 is mounted in a boss 91 secured on the top angle bar I6 of the machine frame structure. An arm 98 is keyed to the shaft 99 intermediate the ends thereof, the arm 98 being identical with the arm 93 which is keyed on the shaft 99.

As best shown in Figure '7, a pin 99 extends through the bars 94 and 95. However, the bar 95 is provided with an aperture I99 having a diameter larger than the diameter of the pin 99. Adjusting screws WI and I92 are threaded through the top and botton, respectively, of the bar 95 for engaging the pin 99. An adjustment of these screws, therefore, effects a vertical movement of the pin 99 in the aperture I99 and causes a slight relative movement between the bars 94 and 95, thereby moving the arms 93 and 98 which are keyed on the shafts 99 and 95, respectively, to adjust the arms into perfect alignment. As shown in Figures 6 and '7, the arms 93 and 98 are extensible by allowing the shaft shown in dotted lines to move downwardly in their housings. These shafts, of course, are secured into the housings during operation of the machine.

The shafts 99 and 96 are grooved across their front face, as at 99a and 960., respectively. These grooves serve as anchoring means for the keys (not shown) used to lock the arms 93 and 99 on the shafts. Since the grooves extend longitudinally on the shafts, the arms 93 and 98 can be moved to engage the ends of a rubber roller of any length.

As best shown in Figures 6 and 7, the ends of the arms 93 and 98 are bifurcated for receiving the axle I93 of the rubber roller I94 that is to be resurfaced.

As best shown in Figures 1 and 6, a member I95 having a horizontal arm I99 extending below the angle beam I 6 and a downwardly sloping arm I91 extending outwardly from the front of the machine is rotatably disposed around the end of the shaft 99. An adjusting screw I 98 is threaded through the anglebeam I9 for acting as a stop for the arm I96 for a purpose to be hereinafter described.

A second member I99 is keyed to the shaft 99 between the boss 9I.and the member I95. The member I99 extends beyond the sloping arm I9? of the member I95, as shown in Figure 6. As best shown in Figure 1, the member I99 is forked at the ends thereof, and a pin II9 (Figure 6) extends between the forked ends of the member I99 and is rotatably mounted in the forked ends.

A threaded adjusting bar II I extends through the pin H9 and is adjusted axially relative to said pin by means of adjusting nuts H2 and H3 which are threaded on the bar II I and abut the collars II9a placed around the bar I II on each side of the pin I I9.

A member H4 is keyed on the right end of the shaft I9, as shown in Figures 1. and 6. The memher I I9 is provided with forked ends (not shown) similar to the ends of the member I99, and a pin H9, similar to the pin H9, is pivotally mounted between the forked ends of the member II4. A coiled spring H9 is disposed around the bar III and held under compression between a collar III formed on the bar and the pin II9. A second coiled spring II! is likewise disposed around the rod II I and held under compression between the nut H8 and the other side of the pin H9.

ihe arm I9'I of the member I95 is slotted, as

shown at I29 (Figure 6) and a bolt I2I extends through this slot and through the member I99. The nuts I I2 and I 53 are adjusted along the rod III to provide the desired compression of the springs H5 and Ill. The bolt I99 extending through the angle beam Itis threaded down a desired distance to act as a stop member to limit the travel of the roller I94 against the sanding roller 45. As pointed out above, the member I95 is freely rotatable around the shaft 99 and can be adjusted by means of the bolt I2I in the slot I29 in relation to the member I99 which is keyed on the shaft 99 so that the elongated arm I 96 will be spaced a desired distance from the stop bolt I99. When the bolt I2I is tightened to secure the member I95 to the member I99, the spring pressure of the springs II 5 and II"! will act against the roller I94 only as long as the arm I96 is spaced from the adjusting bolt I98. When this arm contacts the end of the bolt, the roller I94 cannot be further urged against the sanding roller 95. This mechanism provides for a preadjusting of the desired amount of material to be taken off the rubber roller during the grinding operation.

During the grinding operation, it is desirable to maintain the rubber roller being ground rotating on an. axis lying in the same horizontal plane with the axis of the sanding roller. This adjustment is made to accommodate rubber'rolls of all sizes by a manipulation of the handwheel 93 which raises and lowers the feeding roller I5 and also rotates the member I54 which acts against the springs H5 and II? to move the rod III and thus rotate the member I99 and the shafts 99 and 99. This movement of the shafts,

of course, causes a movement of the roll support-' ing arms 93 and 98 so as to maintain the ends of the same just above the axis of the sanding roller 95 and thereby hold the rubber roll to be ground in the desired position.

As pointed out above, the sanding roller 45 has wound therearound an abrasive sheet 99, such as sandpaper or emery cloth. This sheet 49, as shown in Figures 1 and 3, is preferably wound diagonally around the periphery of the roller 45,

beginning with the end I'III (Figure 14) which is threaded through a slot I'II in the roller 45 at one end thereof and clamped between a bar I72 and the inside of the roller 45 by a bolt I13. With the end of the strip so fixed, the remainder of the strip is readily wound beginning from the left end of the roller diagonally toward the right end with the windings adjoining each other to provide a smooth surface over the entire periphcry of the roller.

According to this invention, a tensioning device I38 is mounted in the roller 55 at the right end thereof, as shown in Figure 5. This tensioning device I30, as shown in Figures 9, 10 and 11, comprises a cylindrical sleeve I3I extending in spaced relation from the periphery of the roller 45 at the inside thereof and away from the end of the roller for a short distance. The sleeve I3I is slotted, as shown at I32, and is provided with an enlarged end I33 encased in a housing I34 which is mounted on the inside periphery of the roller 45. The other end of the sleeve I3! is mounted in a block I35 secured to the'inside periphery of the roller 55 at the end of the roller. The sleeve I3I is rotatable in the housing I35 and block I35. The enlarged portion I33 of the sleeve I3I is secured to the end of a spiralled spring I36 which is encased in the housing, as shown at I31. The other end of the spring I36 is secured to the housing I34, as shown at I38 (Figure 11).

As shown in Figure 9, a slot I39 is provided in the roller above the tensioning device I36. The other end I80 of abrasive strip 45 that is wound around the periphery of the roller is threaded through this slot I39 around the sleeve I3I and through the slot I32 in the sleeve.

The sleeve I3I (Figures 9 and 11) has a square opening I II extending therethrough. (A squarenosed wrench (not shown) may be inserted in the end of the sleeve to engage the square opening MI, and the tension device thereby readily rotated to tighten the spring I36.) The end I40 of the abrasive winding 46 is next threaded, as shown in Figure 9, through the slot I32, and the strip 46 is held tightly around the roller 55 and sleeve I3I by the spring I35.

I have also provided an attachment for the machine to hold the rubber roller in proper position in the nip between the feed roller I5 and the sanding roller 55. In the grinding of small diameter rolls, especially rolls which are light in weight, there is a tendency for the rolls to jump during the grinding operation. In order to overcome this jumping motion, I have provided a holding device, as shown in Figures 12 and 13, which can be supported from the shafts 98 and 96 which also support the ams 93 and 98 engaging the ends of the rollerbeing ground. Thisholding device is useful when the roller being ground is extremely long and cannot be firmly held against the sanding roller by merely supporting the axle of the roll at the ends thereof by means of the arms 93 and 98. This device may also be used in place of the arms 93 and 98.

As shown in Figures 12 and 13, a pair of small diameter rollers I5il are rotatably mounted on an axle I5Ua. The axle I5Ila is supported by an arm I5I which is pivotally mounted at I53 in a supporting member I54. A plate I55 is bolted to the supporting member I54 at I55 and serves to engage the end of the arm I5I to prevent the same from moving upward beyond the elastic limits of a spring I52 which urges the arm I5I downwardly. The spring I521 is at all times maintained in contact with the arm I5I and is compressed by adjusting the supporting member I54 vertically in the groove I51 of a carrying member I53 which is disposed around the shaft 90. As shown in Figure 13, the supporting member I 54 is slotted at I59 and a bolt I60 extends through the slot and is threaded into the member I58. The member I58 is keyed by a key I6I to the shaft 90. The key IIiI is held in a slot in the shaft 90 by the bolt I69. A collar IE2 is threaded on the bolt IBI! and serves to clamp the member I54 in proper adjusted position on the member I55. It should be understood that a duplicate set of the holding rollers I59 are provided near the other end of the machine and are supported from the shaft 95 of the machine in the same manner as the above described rollers are supported from the shaft 90.

As shown in Figure '12, when a roll I53 having a large diameter is being ground, the holding rollers I50 are raised by loosening the collar I62 and raising the member I5 2 in the slot I593. The handwheel is rotated to lower the feeding roller I5. Tins movement also causes an outward movement of the supporting arms 93 and 98 and the holding down mechanism described above. In the grinding operation, it is desirable, as pointed out above, to maintain the roller being ground rotating about an axis lying in the same horizontal plane with the axis of the grinding roller. Therefore, the feeding roller is adjustable vertically so that it can be raised and lowered to rotate the peripheries of various sized rolls so that their axes will be in the desired planes. Because a large sized roll requires a lowering of the feeding roller, the adjusting mechanism is so arranged that the holding down mechanism and supporting mechanism will be moved outwardly during the same operation to engage the rubber roller. It follows that the axles of large diameter rolls will be maintained in a different position from the position maintained by the axles of the small diameter rolls. Therefore, a movement of the feed roller to adjust the machine for large sized rolls also causes the proper movement of the supporting arms and holding down mechanism. Each of these supporting arms and holding down mechanism are further adjusted by means of the additional devices described above to compensate for any unequalities in the roll that is to be ground.

As best shown in Figures 2, 3 and 4, a bin I10 encases the top half of the periphery of the sanding roller 5. This bin I79 is adapted to collect the particles abraded from the roller being ground, and comprises a fiat top III, a vertical back I12 disposed across the back end of the machine and having an opening I13 at the bottom thereof covered with a plate IN. The bottom of the bin IIil slopes upwardly from the back of the machine, as shown at I75 (Figure 4), and terminates in spaced relation from the periphery of the sanding roller 45. The top III of the bin I'Ill has a sloping portion I16 which extends toward the front of the machine just above the sanding roller. A blower II'I, driven by a motor I18, creates a downward draught of air toward the bottom of the bin which sucks air and abraded particles surrounding the periphery of the sanding wheel into the bin. The draught of air created by the blower I'll is not strong enough to blow the abraded particles upward and the bin I70 therefore acts as a cyclone separator permitof the bin where they may be removed through the opening I13. The air is recirculated to the blower through a duct I79.

From the above description it is evident that I have provided a machine adapted to resurface rollers, such as rubber rollers of any diameter or length by feeding the periphery of the roller against a sanding roller which acts on the entire length of the roller to be ground at one time. Supporting devices and holding down devices for the roller being ground are provided to operate in conjunction with the feeding roller for adjusting the machine to fit rollers of different diameters or lengths. The sanding roller is vibrated axially during its rotation to prevent the formation of grooves or hill and valley portions on the roller being ground, due to unevenness in the abrading material.

The abraded particles are collected in a cyclone separator and may be used for the molding of new rubber rollers. The adjusting features of my machine make possible a micrometer adjustment so that the roll being resurfaced can be provided with a very true, accurate and smooth working surface. The machine is operated at high speed and rollers up to 72 inches in length may be ground in about four to ten minutes, whereas heretofore several hours have been required for a resurfacing operation on a large sized roll.

I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

1. A grinding machine comprising a frame structure, an elongated abrasive roller rotatably mounted in said frame structure, a motor for rotating said roller, a shaft mounted on the front of said frame structure and extending across the front of the machine below the abrasive roller, arms secured to said shaft near the ends thereof, a feeding roller rotatably mounted at the ends thereof in said arms, a chain drive encased in one of said arms for rotating the feed roller, a motor for actuating said chain drive, and manual means for rotating said shaft to move the arms thereon and raise and lower the feeding roller relative to the abrasive roller.

2. In a grinding machine, a frame structure, a grinding roller rotatably mounted in said frame structure, a shaft extending about halfway across the front of said frame structure and mounted in straps carried by the frame, a second shaft similarly disposed across the other half of the frame structure in alignment with the first mentioned shaft, arms carried by said shafts slidable along the shafts, means for locking said arms in adjusted position on the shafts, a pair of juxtaposed bars each secured to the end of a shaft and extending outwardly therefrom, an enlarged aperture in one of said bars, a pin secured in the other of said bars and extending into the enlarged aperture of the other bar in spaced relation from the walls defining the aperture, set screws threaded through the apertured bar to engage the pin whereby one of said shafts can be slightly rotated relative to the other shaft for perfectly aligning the arms carried by each shaft.

3. In a grinding machine, a frame, a grinding roller, a pair of aligned slotted shafts each extending halfway across the front of the frame, straps carried by the frame for mounting said shafts on the frame, an arm keyed in the slot of each shaft and adapted to be slid longitudinally along the shafts, means securing the adjoining ends of said shafts together, an adjusting device cooperating with said means to slightly rotate one shaft relative to the other for aligning the said arms, and. spring means for rotating." said shafts as a unit. a.

4. A roll grinding machine 'comprising a frame structure, a grinding roller rotatably mounted therein, a feed rollerrotatably mounted in front of said grinding roller, holding means for mounting a roll to be ground in the nip'betweenthe grinding roller and feed roller, spring means acting on said holding means, meansfor'raising and lowering said feed roller relative to said"grinding roller, said means also moving said holding means into proper position above the nip between the feed and grinding rollers. 1

5. A grinding machine for surfacing rollers comprising an elongated grinding roller having a peripheral abrasive surface at least as long as the roller to be ground, a feed roller in spacedrelation in front of said grinding. roller for-supporting the roller to be groundin the nip between the feeding and grinding rollers, supports for holding the roller to be ground in said nip, a spring device urging said supports against the roller being ground, and a stopmember for said.

spring device preventing the device from acting on the supports when the roll being ground has been abraded to a predetermined degree.

6. A grinding machine for surfacing rubber rollers and the like comprising a base, a frame structure secured to said base, a main driving motor on said base, an auxiliary motor on said base, a grinding roller rotatably mounted in said frame structure on a non-rotatable axle, means driven by the auxiliary motor for oscillating said axle, means transmitting the oscillations of the axle to the roller, a grooved pulley secured to said roller, belts connecting said pulley with said main motor to drive the roller, a feed roller rotatably mounted in front of said grinding roller, means for raising and lowering said feed roller and a chain drive actuated by said auxiliary motor to rotate the feed roll.

'7. A grinding machine for surfacing rubber rollers and the like comprising a grinding roller, a feed roller disposed in front of said grinding roller, means for holding the ends of a rubber roller to be ground in the nip between said rollers, an adjustable stop device to limit the extent of movement of the rubber roller againstthe grind ing roller and a detachable holding down device for acting against the intermediate portion of the rubber roller to prevent the roller from jumping during the grinding operation.

8. In a grinding machine for surfacing rubber rollers and the like, a grinding roller having a peripheral abrasive surface adapted to receive thereagainst the entire length of a roller to be ground, a feed roller in front of said grinding roller for supporting a roll to be ground in the nip between the feed roller and grinding roller, means for driving said feed roller to rotate the roll to be ground against the abrasive surface of the grinding roller, a shaft below said feed roller, arms extending from the shaft to engage the ends of the feed roller for rotatably supporting the roller, and means for rotating said shaft to raise and lower the feed roller relative to the grinding roller and thereby adjust the level of the roll being ground against the grinding roller.

9. A grinding machine comprising a frame, a grinding roller rotatably mounted therein, a shaft extending across the front of the frame near the top thereof, arms adapted to he slid along said shaft keyed against-rotation on the shaft, extensible means on said arms adapted to engage the axles on the ends of a rubber roller to be ground, a forked bracket keyed to one end of said shaft, a rod pivoted in said bracket, a second shaft extending across the front of said frame, arms keyed to said second shaft, a feed roller rotatably mounted at the ends thereof in said arms, a forked bracket keyed to the end of said second shaft for receiving the rod therethrough in pivotal relation, coiled springs disposed around said rod urged against the bracket, means for adjusting the compression of said springs, nuts threaded on the upper portion of said rod to ad- .just the rod longitudinally in the brackets for across the front of said frame near the top thereof, brackets keyed to said shaft, tracks formed in the front face of said brackets, bars mounted in said tracks, means for locking said bars in adjusted position on said brackets, arms pivoted to the ends of said bars, rollers rotatably mounted on the ends of said arms, and spring means urging said arms downwardly so that the rollers thereon are urged against the periphery of a rubber roller to be ground to hold the roller in proper position in the machine.

11. A machine for surfacing rollers comprising an elongated grinding roll adapted to receive thereagainst the entire length of a roll to be ground, a feed roll in spaced parallel relation to the abrasive roll, supporting arms for the ends of said feed roll, a shaft keyed to the ends of said arms, means for rotating the feed roll relative to the supportingarms, means for rotating the supporting arms about the shaft for raising and lowering the feed roll, and separate spring urged means for holding the roll to be ground in the nip between the feed roll and the abrasive roll.

EDWARD HUTCHENS. 

